In other systems, a voltage supply of a control unit faults may be recognized in the voltages used for supplying the components of the control unit, and then the function of the components of the control unit may be interrupted via a RESET line from a supply module, resulting in a shutdown. The voltages are monitored for faults using bands around a specified quantity.
German Published Patent Application No. 44 36 372 discusses a circuit arrangement for an electronic regulating system for motor vehicles, where monitoring of the power supply is provided. If a fault is detected, the regulation is switched over or switched off. An interrupt signal to a monitoring processor is taken into account in the analysis of the monitoring signals. Signal lines are provided, which conduct monitoring signals and test signals to a logic. German Published Patent Application No. 39 28 537 discusses a CAN bus, which connects control units to one another. The resettability of a bus module is monitored. The reset procedure is performed repeatedly in a loop. A time-out counter defines the reset time. Within this time, a check determines whether the reset status has been set. German Patent No. 198 18 315 discusses the provision of independent reference voltages. A supply module generates the required voltages and is resettable.